Gear finishing machine



Jan. 21, 1964 A. H. KETZLER GEAR FINISHING MACHINE 5 Sheets-Sheet 1 Filed April 13, 1959 fill!!! III INVENTOR.

&////// ALMARON H. KETZLER BY M z (W ATTOR Jan. 21, 1964 Fi l'gd April 13, 1959 A. H. KETZLER GEAR FINISHING MACHINE a sheets-sheet 2 LER ATTgNEYS Jan. 21, 1964 A. H. KETZLER 3,113,343

GEAR FINISHING MACHINE Filed April 13, 1959 3 Sheets-Sheet 5 FIG.4.

INVENTg ALMARON H KETZLEQ ToRN 5 United States Patent 3,118,343 GEAR FINEHENG MACHINE Almaron H. Ketzler, Grosse Pointe Farms, Mich, assignor The present invention relates to a gear finishing machine, and more particularly, to feed mechanism employed therein.

It is an object of the present invention to provide feed mechanism which is automatically operable to carry out a feeding cycle in a machine tool to effect successive movements between a work piece and a tool from a clearance or loading position to an initial cut position, to suecessive incremental feed positions, and finally to return the parts to loading or clearance position.

It is a further object of the present invention to provide mechanism for producing periodic incremental feed followed by retraction from final cut position to initial position including an adjustable abutment to limit each incremental feed step to a definitely predetermined amount.

It is a further object of the present invention to provide in a machine tool automatic feed mechanism including simple manually operable means to disable the automatic feed mechanism to provide for manual movement of the parts into adjusted position.

Other objects and features of the invention will become apparent as the description proceeds, especially when taken in conjunction with the accompanying drawings, illustrating a preferred embodiment of the invention, wherein:

FIGURE 1 is a front elevation of a gear finishing machine to which the present invention is applied.

FIGURE 2 is a fragmentary vertical section through the table and feed mechanism of the gear finishing machine with the automatic feed mechanism omitted.

FIGURE 3 is a plan view with parts broken away and partly in section of the automatic attachment to the machine illustrated in FIGURES 1 and 2.

FlGURE 4 is a sectional view on the line 4--4, FI v URE 3.

The present invention relates to feeding mechanism broadly and may be applied to any machine tool in which it is desired to carry out a cycle including successive feeding steps. For purposes of illustration however, the invention is illustrated as applied to a gear finishing machine, and more specifically, as an attachment for use on a gear finishing machine.

Referring now to FIGURES l and 2 there is shown a gear finishing machine which comprises a main frame it having an overhanging head 12 provided with an adjustable cutter head 14. At the front of the machine there is provided a vertically adjustable knee 16, a suitable feed screw device indicated generally at 13 being provided for effecting vertical movement of the knee. The gear finishing machine includes a siideway 22 on which is mounted a horizontal table 24 for horizontal reciprocation. The table includes head and tailstocks 26 between which a rotary work piece such for example as a gear is mounted.

As best seen in FIGURE 2 the feed screw mechanism includes a feed screw 27 which is rotatable by suitable mechanism for effecting vertical adjustment of the knee 16. Secured to the upper end of the feed screw is a worm gear 28 which meshes with a worm 3i) carried by a shaft 32 terminating at the front of the machine in a square end as indicated at 34 for rotation by a suitable hand tool. The present invention comprises mechanism adapted to be associated with the shaft 32 in such away as to 3,ll&343 Patented Jan. 21, 196% effect automatic controlled rotation thereof to effect ver tical movement of the knee to carry out a complete finishing cycle. This cycle involves a vertically upward movement of the knee from a clearance or loading position in which a gear carried by the stocks 26 may be in loose mesh with a gear-like cutter carried by the cutter head 14. This movement may be substantial and is intended to bring the gear and cutter into tight mesh or to establish an initial cut position. Thereafter, the table 24 is traversed horizontally to effect a out while the gear and gear-like tool are driven in rotation, after which there will be provided one or more additional incremental rotations of the feed screw 27 to carry out successive cuts. Following this there may be one or more strokes of traverse of the table 24 without additional infeed, these being idle strokes or finishing strokes to complete the gear finishing operation. Finally, the feed screw will be reversely rotated to lower the knee 16 to its clearance or loading position.

The mechanism for carrying out these functions is illustrated in FIGURES 3 and 4. The structure comprises a drive shaft 4% which replaces the shaft 32 and which is provided with the worm 30 which meshes with the worm gear 28, best seen in FIGURE 2. The shaft 40 has rigidly connected thereto a ratchet disc 42 and a pinion 44, these parts being keyed as indicated at 46 and 48 respectively. Mounted for rocking movement on a hub portion 50 of the ratchet disc 42 is an actuating lever 52. Mounted on the lever 52 for swinging movement by a pivot connection indicated at 54 is a pawl 56 having a tooth 58 engageable with correspondingly shaped teeth on the ratchet disc 42,. The pawl is biased in a counterclockwise direction by a spring 59.

The pawl 56 includes an arm 60 engageable with a pin 62 when the actuating lever 52 is swung counterclockwise. It will be observed that engagement between the arm 60 and pin 62 during counterclockwise swinging movement of the lever 52 will have the effect of withdrawing the tooth 58 from the toothed periphery of the ratchet disc 42.

A fluid motor is provided which is herein illustrated as a cylinder 64 containing a piston connected to a piston rod 66. The piston rod 66 has a pivot connection 63 to a head 6h on the free end of the actuating lever 52, and to accommodate swinging movement of the parts the cylinder is provided with a pivot mounting indicated at 76.

Located adjacent the head 69 of the actuating lever 52 is an adjustable abutment 72 which is angularly adjustable about a pivot support indicated at 74 to bring one of four abutment faces into operative relation. The abutment member 72 bears indicia herein designated 1, 2, 3 and 4, to indicate the amount of upfeed of the knee which will result when the corresponding abutment surface is in operative position.

Associated with the pinion 44- is an elongated and longitudinally slidable rack 76 having rack teeth 78 at one side thereof engageable with the teeth of the pinion 44-. The rack 76 is connected by a piston rod 8% to a piston within a return cylinder 82. The right hand end of the rack 76, as seen in FIGURE 3, is provided with a short section indicated generally at 84 provided with circumferentially extending round rack teeth 86 and this portion of the rack is cut away to provide the fiat surface 88 for a purpose which will subsequently appear.

With the foregoing construction, automatic operation of the machine involves rotation of the gear and gearlike tool in mesh accompanied by traverse of the table '24 to distribute finishing action of the tool from end to end of the gear teeth. Means are provided for controlling the flow of fluid under pressure to the cylinders 64 and 82 in proper relation to the gear finishing cycle. Specifically, at the end of each stroke or reciprocation of the Q) table, fluid is admitted to the right hand end of the cylinder 64 as viewed in FIGURE 3, thus swinging the actuating lever 52 clockwise through an are determined by engagement between its head and the selected abutment surface of the abutment member 72. During this movement the tooth 58 of the pawl 56 will effect a predetermined rotation of the ratchet disc 42,

The parts are shown in FIGURE 3 in an intermediate position. Assuming that the piston in the cylinder 64 is moving to the right, the tooth 58 of the pawl 56 wii ride over the inclined teeth of the ratchet disc 42 until such time as its arm 60 engages the pin 62. Thereafter, further movement of the actuating lever 52 results in rocking movement of the pawl 56 relative thereto in a direction to withdraw the tooth 58 from the toothed periphery of the ratchet disc 42. When the piston in the cylinder 64 is moved to the left, at an intermediate point in its stroke the arm 60 of the pawl is permitted to swing to move the tooth 58 into engagement with the ratchet disc. Thereafter, further movement effects clockwise rotation of the ratchet disc and a corresponding rotation of the shaft 40 which results in upfeed of the knee 16 of the machine.

Since the pinion 44 is fixed to the shaft 40, feeding rotation of the shaft 40 in a clockwise direction will result in movement of the rack 76 to the right, thus moving the piston in the cylinder 82. When the finishing action is completed to the required depth, the ratchet disc 42 will have moved into a position in which a guard plate 90 is in position to prevent engagement between the tooth 58 of the pawl 56 and the teeth of the ratchet disc 42. This will prevent further vertical movement of the knee and thereafter one or more traverse strokes of the table may be provided to effect a finishing action on the teeth of the gear. When the required finishing action is completed the knee is returned to its initial lower position to provide for removal of thl finished work gear and its replacement by a succeeding work gear to be finished. It will be recalled that when the piston in the cylinder 64 is moved to the right following each feeding stroke, the pawl 56 is disengaged from the ratchet disc 42. Accordingly, at this time when fluid under pressure is admitted to the right hand end of the piston in the cylinder 82, the rack 76 moves to the left and effects counterclockwise rotation of the pinion 44, the ratchet disc 42, and the shaft 40, thus dropping the knee to its initial position.

The mechanism is constructed and arranged to provide for manual adjustment of the machine to accommodate gears of different size and to provide for setting of the machine prior to running a series of identical gears. For this purpose the shaft 49 is provided with a squared end as indicated at 92 for engagement by a hand tool. The squared end 92 of the shaft is received in a cup-like member 94 the end surface 96 of which is preferably provided with indicia adapted to be associated with a stationar} pointer a portion of which is indicated at 98. Accord ingly. the elevation of the knee may be controlled to very close limits.

In order to accommodate manual vertical adjustment of the knee, means are provided for effecting disengagement between the rack 76 and the pinion 44. This means con t3.i5es the cut away portion at the end 34 of the rack which provides the hat surface 88. The rack 76 is rotatable about its longitudinal axis and is provided with a handle 19!) extending laterally therefrom. When the mechanism has been operated to bring the round teeth 86 of the rack into mesh with the pinion 44, the rack may be rotated to bring the flat surface 88 thereof downwardly and thus to disengage the teeth of the pinion 44 therefrom. At this time the shaft 43 may be rotated by hand to effect large changes in height of the knee and also to effect fine adjustment thereof. When the knee has thus been brought into the required position the rack may be rotated to engage its teeth with the teeth of the pinion. It will be observed that this disengagement be 4 tween the teeth of the rack and pinion occurs when the rack is in its extreme position to the left, which corresponds to the lowered position of the knee or the position which the knee occupies at the beginning of the automatic cycling It will of course be appreciated that the means for supplying fluid to the cylinders 64 and 82 may be controlled by suitable valves which in turn may be controlled by limit switches actuated by the movement of the table 24. Initial upfeed of the knee from a loading position to an initial cut position may if desired be produced by repeated actuation of the cylinder 64 prior to initial traerse of the table.

In accordance with the present invention, the automatic cycling of the machine includes accurately prcdctermined equal increments of feed taking place between traverse strokes of the table and continued until the knee ias been raj ed a height corresponding to the required final gear dimension. Thereafter, following one or more idle strokes without additional infeed if desired, the knee is dropped to its initial position preparatory to unloading a finished work gear and replacing a new work gear on the machine.

The present construction is intended for use primarily with automatically operated machines in which a supply of gears is provided and is automatically loaded onto the machine serially and removed therefrom without requiring attention of operator. The automatic cycling continues so long as a supply of gears remains to be finished. The present automatic feeding apparatus is characterized by its Xtreme simplicity and its reliability in operation, factors which are required in connection with fully automatic machines.

The drawings and the foregoing specification constitute a description of the improved gear finishing machine in such full, clear, concise and exact terms as to enable any person skilled in the art to practice the invention, the scope of which is indicated by the appended claims.

What i claim as my invention is:

1. Automatic feed mechanism for a machine tool comprising a rotatable feed member, a ratchet disc connected to said member, a pawl engageable with said disc and mounted for repeated forward movements to advance said met her for corresponding repeated reverse movements to move over said disc for subsequent engagement therewith at a different point, means operable upon a predetermined amount of each reverse movement of said pawl to disengage said pawl from said disc, first power means for moving said pawl repeatedly forwardly and reversely at intervals to effect incremental feed, and second power means separate from said first power means operable while said pawl is disengaged to rotate said feed member reversely to starting position.

2. Automatic feed mechanism for a machine tool comprising a rotatable feed member, power feed means comprising a pawl and ratchet mechanism for effecting incremental advance of said member, means operable automatically after each successive feed operation to disconnect said ratchet mechanism, power return means operable following a final feed operation to return said member to starting position, means for disconnecting said return means from said member, said member being manually rotatable when said return means and ratchet mechanism (re disconnected.

3. Automatic feed mechanism for a machine tool comprising a feed member rotatable in forward direction to effect a feeding operation between a tool and work piece and in a reverse direction to restore the tool and work piece to starting positions, a ratchet disc connected in driving relation in forward direction to said member, an actuating lever mounted for rocking movement about the axis of said disc, a pawl on said lever cngageable with said disc, power feed means for swingin said lever repeatedly in forward and reverse directions to advance said ratchet disc and member in increments, means engageablc by said pawl during each reverse movement of said lever to retract said pawl from said disc, and power return means separate from said power feed means operable while said pawl is retracted to rotate said feed member reversely to starting position.

4. Automatic feed mechanism for a machine tool comprising a feed member rotatable in forward direction to effect a feeding operation between a tool and work piece and in a reverse direction to restore the tool and work piece to starting positions, a ratchet disc connected in driving relation in forward direction to said member, an actuating lever mounted for rocking movement about the axis of said disc, a pawl on said lever engageable with said disc, power feed means for swinging said lever repeatedly in forward and reverse directions to advance said ratchet disc and member, an adjustable abutment effective to limit forward swing of said lever to control the amount of feeding movement of each feeding operation, means engageablc by said pawl during each reverse movement of said lever to retract said pawl from said disc, and power return means separate from said power feed means operable while said pawl is retracted to rotate said feed member reversely to starting position.

5. Automatic feed mechanism for a machine tool comprising a feed member rotatable in forward direction to effect a feeding operation between a tool and work piece and in a reverse direction to restore the tool and work piece to starting positions, a ratchet disc connected in driving relation in forward direction to said member, an actuating lever mounted for rocking movement about the axis of said disc, a pawl on said lever engageable with said disc, a fluid piston and cylinder unit for swingsaid lever repeatedly in forward and reverse directions to advance said ratchet disc and member incrementally, means engageable by said pawl during each reverse movement of said lever to retract said pawl from said disc, and power return means operable while said pawl is retracted to rotate said feed member reversely to starting position.

6. Automatic feed mechanism for a machine tool comprising a feed member rotatable in forward direction to effect a feeding operation between a tool and work piece and in a reverse direction to restore the tool and work piece to starting positions, a ratchet disc connected in driving relation in forward direction to said member, an actuating lever mounted for rocking movement about the axis of said disc, a pawl on said lever engageable with said disc, power feed means for swinging said lever in forward and reverse directions to advance said ratchet disc and member, means engageable by said pawl during reverse movement of said lever to retract said pawl from said disc, a pinion connected to said member, a rack connected to said pinion, and power return means separate from said power feed means connected to said rack operable while said pawl is retracted to rotate said feed member reversely to starting position.

7. Automatic feed mechanism for a machine tool comprising a feed member rotatable in forward direction to effect a feeding operation between a tool and work piece and in a reverse direction to restore the tool and work piece to starting positions, a ratchet disc connected in driving relation in forward direction to said member, an actuating lever mounted for rocking movement about the axis of said disc, a pawl on said lever engageable with said disc, a power unit for swinging said lever in forward and reverse directions to advance said ratchet disc and member, means engageable by said pawl during reverse movement of said lever to retract said pawl from said disc, a pinion connected to said member, a rack connected to said pinion, and fluid piston and cylinder return means connected to said rack operable while said pawl is retracted to rotate said feed member reversely to starting position.

8. Automatic feed mechanism for a machine tool comprising a feed member rotatable in forward direction to effect a feedin operation between a tool and work piece and in a reverse direction to restore the tool and work piece to starting positions, a ratchet disc connected in driving relation in forward direction to said member, an actuating lever mounted for rocking movement about the axis of said disc, a pawl on said lever engageable with said disc, a power unit for swinging said lever in forward and reverse directions to advance said ratchet disc and member, means engageable by said paid during reverse movement of said lever to retract said pawl from said disc, a pinion connected to said member, a rack connected to said piston, power return means connected to said rack operable while said pawl is retracted to rotate said feed member reversely to starting position, said rack having a portion of circular cross-section provided with teeth extending circumferentially thereon, a relieved section on said portion in which the teeth are removed, means for rotating said rack about its axis to disconnect said rack and pinion, said member being manually rotatable when said rack and pinion, and pawl and ratchet are disconnected.

References Qited in the file of this patent UNITED STATES PATENTS 

1. AUTOMATIC FEED MECHANISM FOR A MACHINE TOOL COMPRISING A ROTATABLE FEED MEMBER, A RATCHET DISC CONNECTED TO SAID MEMBER, A PAWL ENGAGEABLE WITH SAID DISC AND MOUNTED FOR REPEATED FORWARD MOVEMENTS TO ADVANCE SAID MEMBER AND FOR CORRESPONDING REPEATED REVERSE MOVEMENTS TO MOVE OVER SAID DISC FOR SUBSEQUENT ENGAGEMENT THEREWITH AT A DIFFERENT POINT, MEANS OPERABLE UPON A PREDETERMINED AMOUNT OF EACH REVERSE MOVEMENT OF SAID PAWL TO DISENGAGE SAID PAWL FROM SAID DISC, FIRST POWER MEANS FOR MOVING SAID PAWL REPEATEDLY FORWARDLY AND 